 /*******************************************************************************
  * Copyright (c) 2005, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.actions;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.jface.action.ControlContribution;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.KeyAdapter;
 import org.eclipse.swt.events.KeyEvent;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.widgets.Combo;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.internal.WorkbenchMessages;
 import org.eclipse.ui.internal.WorkbenchPlugin;

 /**
  * This is the contribution item that is used to add a help search field to
  * the cool bar.
  *
  * @since 3.1
  */
 public class HelpSearchContributionItem extends ControlContribution {
     private static final String ID = "org.eclipse.ui.helpSearch"; //$NON-NLS-1$

     private IWorkbenchWindow window;

     private Combo combo;

     private int MAX_ITEM_COUNT = 10;
     
     /**
      * Creates the contribution item.
      *
      * @param window the window
      */
     public HelpSearchContributionItem(IWorkbenchWindow window) {
         this(window, ID);
     }

     /**
      * Creates the contribution item.
      *
      * @param window the window
      * @param id the contribution item id
      */
     public HelpSearchContributionItem(IWorkbenchWindow window, String id) {
         super(id);
         Assert.isNotNull(window);
         this.window = window;
     }

     /* (non-Javadoc)
      * @see org.eclipse.jface.action.ControlContribution#createControl(org.eclipse.swt.widgets.Composite)
      */
     protected Control createControl(Composite parent) {
         combo = new Combo(parent, SWT.NONE);
         combo.setToolTipText(WorkbenchMessages.WorkbenchWindow_searchCombo_toolTip);
         String [] items = WorkbenchPlugin.getDefault().getDialogSettings()
                 .getArray(ID);
         if (items != null) {
             combo.setItems(items);
         }
         combo.setText(WorkbenchMessages.WorkbenchWindow_searchCombo_text);
         combo.addKeyListener(new KeyAdapter() {
             public void keyReleased(KeyEvent e) {
                 if (e.character == SWT.CR) {
                     doSearch(combo.getText(), true);
                 }
             }
         });
         combo.addSelectionListener(new SelectionAdapter() {
             public void widgetSelected(SelectionEvent e) {
                 int index = combo.getSelectionIndex();
                 if (index != -1) {
                     doSearch(combo.getItem(index), false);
                 }
             }
         });
         return combo;
     }

     /* (non-Javadoc)
      * @see org.eclipse.jface.action.ControlContribution#computeWidth(org.eclipse.swt.widgets.Control)
      */
     protected int computeWidth(Control control) {
         return control.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x;
     }

     private void doSearch(String phrase, boolean updateList) {
         if (phrase.length() == 0) {
             window.getWorkbench().getHelpSystem().displaySearch();
             return;
         }
         if (updateList) {
             boolean exists = false;
             for (int i = 0; i < combo.getItemCount(); i++) {
                 String item = combo.getItem(i);
                 if (item.equalsIgnoreCase(phrase)) {
                     exists = true;
                     break;
                 }
             }
             if (!exists) {
                 combo.add(phrase, 0);
                 if (combo.getItemCount() > MAX_ITEM_COUNT) {
                     combo.remove(combo.getItemCount() - 1);
                 }
                 WorkbenchPlugin.getDefault().getDialogSettings().put(ID,
                         combo.getItems());
             }
         }
         window.getWorkbench().getHelpSystem().search(phrase);
     }
 }

